• Applied Biological Chemistry
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• v.51 no.1
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• pp.84-87
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• 2008

In this research, we screened for glucosyltransferase (GTase) inhibitors that effectively prevent the dental caries from 420 kinds of boiled water extracts of herbs and wild plants and searched for GTase inhibitory activities. Among them, 13 kinds of hot water extracts had high GTase inhibitory activities and especially, we focused on Foeniculum vulgare which showed the highest inhibitory activity on GTase. The boiled water extract of F. vulgare was stable at high temperature and showed as a mixed type of competitive and uncompetitive inhibition kinetic behavior. It did not have antibacterial effect on Streptococcus mutans and had inhibitory activity on GTase. Specially, in the clinical trial, the group treated by boiled water extract of F. vulgare showed more decrease of plague index at 4.8 point than untreated group. These results suggested that boiled water extract of F. vulgare can effectively suppress the plague formation as it inhibits the GTase activity.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.4
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• pp.265-271
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• 2004

This study was carried out to furnish basic information on the habitat through soil condition and vegetation structure of an Acer mono for. rubripes stand in Geoje, Gyeongnam Province. Soil pH of the A. mono for. rubripes stand was 5.17. The contents of organic matter, total N and available P205 were 8.7%,0.38%, 15.7ppm, respectively. A. mono for. rubripes, Meliosma oldhamii, Zelkova serrata, Styrax japonica, Sapium japonicum, Lindera erythrocarpa and Euonymus oxyphyllus appeared in all layers. The importance values of A. mono for. rubripes, Z. serrata and Quercus serrata in the upper layer were high, S. japonicum and M. myriantha were high in the middle layer and lower layer, respectively. Species diversity and evenness ranged from 0.931 of the middle layer to 1.638 of the lower layer, and from 0.706 of the upper layer to 0.959 of the lower layer, respectively. The study results provide basic information on soil condition and vegetation structure of the Acer mono for. rubripes stand native to Geoje, Korea.

• Journal of Korean Society of Forest Science
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• v.101 no.1
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• pp.62-68
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• 2012

We have investigated needle life span, photosynthetic pigment and nitrogen allocation pattern in the needle of Picea jezoensis in the three populations (Gyebangsan, Deogyusan and Jirisan) to find out growth environmental condition which needs the strategy development of conservation and restoration against population decline. Needle survival rate was the highest in Gyebangsan (87.0%) and the lowest in Jirisan (71.6%), and it decreased with the increase of needle age. Needle chlorophyll a and b in Deogyusan and Jirisan showed higher content in older needle, but chlorophyll content in Gyebangsan was the highest in 2-year-old needle. Carotenoid content was the highest in the needle in Gyebangsan, and it increased along with needle age. Chlorophyll a/b ratio showed the highest value in Jirisan and the lowest value in Gyebangsan. Chlorophyll/carotenoid ratio decreased with needle age, Needle nitrogen content was the highest in Deogyusan (1.51%) and the lowest in Gyebangsan (1.40%), and the older needle had the lower content. In contrast, the highest chlorophyll/nitrogen ratio represented the oldest needle.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.1
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• pp.8-14
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• 2000

Long term cultivation crops like tomato, capsicum, melon etc. demand much amount of continuous supplying of nutrition during the whole growing periods. It is not easy to cover satisfactorily the nutritional demands for them by splitted top dressings, slow release fertilizer applications and fertigation systems. To overcome these problems, the "CULTAN" (Controlled Uptake Long Term Ammonium Nutrition) Beaker Deposit techniques have been developed and it was put into PVC beaker with the combined nitrogen fertilizer type mixed with the ratio of one-third of ammonium sulfate-N and two-thirds of urea-N, in which nitrogen was loaded on the demanding amount of a tomato plant during the growing period. Gypsum was mixed as a binder, and loamy soil and compost were used as a diffusion regulator. It was placed upside down into root zone of tomato at the transplanting. Tomato roots were spreaded into the Deposit beaker by ammonium ions which attract root growth. The tomato fruit yield and nitrogen uptake by plant were increased by application of $NH_4$-Beaker deposit fertilizer rather than those of common fertilizer treatment. In conclusion, it was able to improve economic and ecological benefits through CULTAN system compared with common fertilization systems. CULTAN system was estimated as a prospective alternative to enhance productivity and minimize nutrient lose. In addition, it shows further developing possibility of CULTAN system by the supplement of micro-nutrients and pesticides in the macro-nutrient beaker deposits.

• Korean Journal of Weed Science
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• v.13 no.1
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• pp.62-70
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• 1993

There was intraspecific variation in Echinochloa crus-galli var, crus-galli in response to quinclorac, showing that plan height and dry weight of a locally collected barnyardgrass(Chinjupi) from Chinju were 90.5 and 37.8% of the untreated control, while those of a locally collected one(Iripi) from Iri showed 19.1 and 14.4%, respectively. The normal distribution curve was obtained from frequency distribution of 89 rice cultivars as affected by the application rates of quinclorac at 30, 300, and 3,000g ai/ha. Protein patterns(SDS-PAGE) of two barnyardgrasses belonging to E, crus-galli var. crus-galli such as Iripi and Chinjupi were not affected by the quinclorac application, indicating that inhibition of enzyme and/or protein biosynthesis seems to be not the primary action target of quinclorac. Electronmicroscopic observation on the injured leaf of Iripi which is considered as a susceptible one showed prominent membrane disruption. Chuchungbyeo(rice variety) resulted in a greater inhibition of tomato growth than those from Chinjupi or Iripi, indicating a great amount of quinclorac discharged from rice root, Chinjupi which is relatively tolerant to quinclorac than Iripi, discharged more quinclorac causing a greater inhibition of tomato growth.

• Weed & Turfgrass Science
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• v.2 no.2
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• pp.184-190
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• 2013

It is important for genetic resources to collect and identify in native medium-leaf type zoysiagrasses species distributed in Korea. This study was conducted to investigate morphological variation and characteristics of native medium-leaf type zoysiagrasses from coastal, island and inland regions in Korea. Among them, 75 collected lines was confirmed to have various morphological variations, accessions were classified into 2 main based group coastal and inland regions by morphological characteristics and site environment. Group I included Z. sinica type, this group showed 3.7 mm in leaf width, 29 in number of seed per spikelet and 5.0 mm in seed length. Group II included Z. japonica type, this group showed 4.4 mm in leaf width, 42 in number of seed per spikelet and 3.5 mm in seed length. There is a need for additional research on growth characteristics and the molecular level for the introgressive hybridization between species which confirmed that cross-pollination is possible due to protogyny. The individuals showing variations should be preserved as valuable genetic resources for the expansion of variations in zoysiagrasses, and the results of this investigation on the genetic resources collected will be highly valuable in breeding high quality turfgrass.

• Weed & Turfgrass Science
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• v.5 no.4
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• pp.196-202
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• 2016

With increasing LM soybean import, the concern about unintentional gene flow from LM soybean to wild soybean and consequential weedy risk has been growing. Therefore, we conducted this study to characterize seed traits including germination of hybrids resulted from gene flow from LM soybean to wild soybean in comparison with their parents, LM soybean and wild soybean. Pollen-donor LM soybean seeds were much greater and heavier (about 15.0 g of 100 seed weight) than F2 hybrid (5.7 g), while pollen-recipient wild soybean and F1 hybrid seeds were smallest and lightest (about 2.5 g). F2 hybrid was brown, intermediate between yellow LM soybean seed and black wild soybean seed. These findings indicate that F1 hybrid seeds show similar characteristics with wild soybean, while F2 hybrid seeds show intermediate color and size between two parents. F2 hybrid seed showed intermediate traits between two parents in germination and dormancy rates, which were 35% and 65%, respectively. LM soybean showed no dormancy, while wild soybean showed greater than 90% dormancy. This finding indicates that F2 hybrid show intermediate characteristics in seed germination with high dormancy trait, suggesting a potential weediness of hybrids resulted from gene flow from LM soybean to wild soybean.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.492-496
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• 2010

This experiment was carried out to obtain the maximum quantity of essential oil on the basis of harvesting time, cultivation regions & types, and drying methods. We have selected 6 native and introduced herbs viz. $Thymus$ $quinquecostatus$, $Agastache$ $rugosa$, $Chrysanthemum$ $indicum$, $Rosmarinus$ $officinalis$, $Chamaemelum$ $nobile$, and $Lavandula$ $stoechas$. The quantity of essential oil ranged from 0.06% to 3.46% in all six herbs. Native herbs produce 30.5% higher quantity of oil in comparison to introduced herbs. The quantity of essential oil obtained from $Lavandula$ $stoechas$ was 3.46%, followed by $Rosmarinus$ $officinalis$ 2.89%, while minimum in $Agastache$ $rugosa$ 0.60%. Higher quantity of essential oil obtained if they are cultivated under rain shelter culture (PE film) in comparison to open field conditions. Recovery of essential oil is always high if herbs flower in July. Semi-alpine region was found better than the plain region for herbs production. Quantity of oil is high if oil is extracted from fresh herbs followed by freezed herbs, shade dry and hot wind dry herbs. As far as plant part is concern flower produced maximum oil than any other part.

• Korean Journal of Ecology and Environment
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• v.36 no.2 s.103
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• pp.191-199
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• 2003

This study was conducted to investigate a seasonal variation of phytoplankton communities at 6 stations in the Hantan River from November, 2001 to August, 2002. Electric conductivity gradually increased from the upper reaches to the down reaches. DO differed not much from the upper reaches to down reaches, but it decreased at the station where the pollutants inflowed. T-N and T-P concentrations were high at station 4${\sim}$6. Chlorophyll-a concentration gradually increased at the mid and down reaches. It was high in May but decreased in August by the heavy rains. Phytoplankton communities were identified a total 354 taxa composed of 99 genus, 320species, 19 varieties, 3 forma and 12 unidentified species. There were 135 taxa of Chlorophyceae, 134 taxa of Bacillariophyceae, and the other taxa were Euglenophyceae, Cyanophyceae, Xanthophycaea, Chrysophyceae and Dinophyceae. Standing crops ranged from 8,600 to 337,100 cells/mL and it was lower in August than May by the rains. Dominant species included Achnanthes alteragracillima, Achnanthes convergens, Achnanthes minutissima and Cymbella minuta var. silesiaca which were the saproxenous species at the reaches, and were Cyclotella meneghiniana, Chlamydomonas pseudopertyi and Nitzschia which were saprophilous and eutrophic species at the down reaches. The correlation coefficients between phytoplankton standing crops and EC, BOD and T-N, T-P was 0.68, 0.60, 0.60 and 0.70, respectively. All correlation coefficients between Chlorophyceae and EC, BOD and T-P were higher than 0.6. A. convergens were negative correlations with EC and BOD, but N. palea were positive with EC, BOD, T-N and T-P.

• Proceedings of the Ginseng society Conference
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• 2005.11a
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• pp.3-18
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• 2005

This paper reports the characteristics of 8 new cultivars for selected from Korean ginseng. The occurance of multi stems were the highest in Yunpoong(45%) and the lowest in Gumpoong(7%), but growth of aerial parts were the highest in Gumpoong and the lowest In Yunpoong among new cultiyars. The ratio of seeds harvest were the highest in Gumpoong(85.4%) and the lowest in Chunpoong(69.1%), but number of seeds per plant were the highest in Yunpoong(108.3ea) and the lowest in Chunpoong(77.5ea) among new cultivars. The ratio of leaf burning were the highest in Chunpoong but the lowest in Yunpoong among new cultivars. In weight distribution of the different parts of the ginseng roots, the ratio of main root were high in Jakyungjong(63.1%) but low in new cultivars(49%-55.9%), but the ratio of lateral root were high in new cultivars(19.3-23.3%), but low in Jakyungjong(13.2%), the ratio of fine root were not different. Root yield declined in the order of Yunpoong, Gumpoong, Gopoong, Chunpoong, Sunpoong, Jakyungjong. The length of main root were the longest in Chunpoong(8,0cm) but the shortest in Yunpoong(6,4cm), The ratio of rusty-root was low in new cultivars(0,2-9,5%), but high in Jakyungiong(16,3%). The grade of red ginseng roots decreased in the order of Chunpoong, Gumpoong, Gopoong, Sunpoong, Yunpoong, Cheongsun, Jakyungjong. The total ginsenoside contents per dry weight in main roots was high in Gumpoong(8.53mg), Yunpoong(8.13mg), Gopoong(7,47mg), but low in Chunpoong(5.73mg), Sunpoong(4.87mg).